A pipeline inspection gage or “pig” is a tool directed through a section of pipeline, typically advanced through the pipeline by the pressure of fluid flow through the pipeline, or other differences in pressure within the pipeline. Pigs may be used to inspect the pipeline with various sensors, to separate fluid flows within the pipeline, to clean the interior surface of the pipeline, to record geometric information about the pipeline, as well as for other purposes. One way to inspect the pipeline is to pass a sensor-carrying pig module (e.g., sensor carrier module) through the pipeline. Transducers mounted to the pipeline pig may be configured to emit ultrasonic signals into the pipeline wall and receive reflected ultrasonic signals, which may be analyzed or processed to detect features (e.g., cracks) in the pipeline.